Method for securing terminals



June 4, 1963 H. F. HILD ETAL 3,091,838

METI-IOD FOR SECURING TERMINALS Filed Oct. 2, 1959 2 Sheets-Sheet 1 3432 20 a 5 7 30-; v I i l I m O l I o: l N L June 4, 1963 H. F. HILD ETALMETHOD FOR SECURING TERMINALS 2 Sheets-Sheet 2 Filed 000- 2, 1959 UnitedStates Patent M 3,091,838 METHQD FOR SECURING TERMINALS Henry F. Hildand Siegfried E. Manecke, Indiana, Pa., as-

signors to Robertshaw-Fulton Controls Company, Richmond, Va., acorporation of Delaware Filed Oct. 2, 1959, Ser. No. 844,100 4 Claims.(Cl. 29-15555) This invention relates to method for securing terminalsto a casing and, more particularly, to securing flat plate maleterminals to a molded plastic casing.

It has been the practice to secure a flanged electrical terminal to arelatively thin-walled casing by overlapping portions of the terminal soas to engage one surface of a wall. Generally, this practice of securinga terminal to a casing has been referred to as staking.

To secure the flanged terminal to an aperture in the casing, 21sharp-edged punch is used to overlap a portion of the body of theterminal, closely adjacent to the periphery of the aperture in thecasing wall, so as to form outwardly extending flanges which secure theterminal to the wall. However, as the terminal is generally made of amalleable metal, such as brass, it is relatively soft and easily splitwhen subjected to shearing stresses. In addition, the sharp-edged punchused for peeling the terminal is not resiliently mounted and, therefore,transmits a high impact shock to the terminal when the sharpedged punchis actuated.

Another difliculty in staking terminals to a thin-walled casing is theextreme accuracy with which the sharpedged punch must be positionedprior to actuation. Generally, the punch has at least two edges thatengage substantially oppositely disposed side portions of the terminal.If the punch is not properly positioned, one edge will engage theassociated side portion of the terminal; while the other edge willengage the surface of the wall of the casing. In this event, the casingcan easily be broken by the impact. Also, should the punch initially bepositioned to unevenly engage opposite sides of the terminal, thenuneven stresses will be imposed upon the terminal upon impact. Theseuneven stresses will be transmitted to the casing to crack the thin wallupon which the terminal is mounted.

An object of this invention is to secure terminals to a thin-walledcasing by peening a portion of the terminal onto the surface of thecasing.

Another object of this invention is to spin a shoulder portion of aterminal onto the upper surface of a thinwalled casing under arelatively light, uniformly distributed impact operation.

A further object of this invention is to fasten electrical terminals toa thin-walled casing in a rapid, inexpensive manner.

Other objects and advantages will be apparent from the followingdescription of the invention taken in connection with the accompanyingdrawings wherein:

FIG. 1 i an elevation view, partly in section, of a terminal positionedin a thin-walled casing;

FIG. 2 is a view similar to FIG. 1 of the terminal and punch;

FIG. 3 is a view of the terminal and punch in operative relationship;

FIG. 4 is an end view, partly in section, of the terminal and punchafter the spinning and peening operation; and

FIG. 5 is a plan view of the terminal after the spinning and peeningoperation.

Referring more particularly to FIG. 1, there is shown a flat terminalpost inserted and positioned in a slit aperture 12 of a thin-walledcasing 14. Thin-walled casing 14 can be molded from any known phenolicplastic having good structural and electrical insulation properties. Theterminal 10 is stamped out of a flat sheet material,

3,091,838 Patented June 4, 1963 such as brass, and may have variousconfigurations, one of which is shown in FIG. 1. The terminal 10, shownin FIG. 1, has a male connector portion 16 extending upwardly of theaperture 12 in the casing 14. The male connector 16 has a length andwidth of suitable dimensions, which dimensions are primarily determinedby the female connector (not shown) that will be used in the electricalcircuit.

A main body portion 18 of the terminal 10 is located beneath the maleconnector portion 16 of the terminal 10 and substantially between thesidewalls 20 of the aperture 12. The main body portion 18 has a widthwhich is slightly greater than the base width of the male connectorportion 16. The depth of the main body portion 18 of the terminal 10 isgreater than the thickness of the wall of the casing 14. A small area oneach side of the main body portion 18 extends above the upper surface 22of the wall of the casing 14, to form shoulders 24.

Beneath the main body portion 18 of the terminal are oppositely disposedflange portions 26 which extend outwardly from the longitudinal lengthof the terminal 10. The flange portions 26 of the terminal '10 are ofsufiicient width and depth to prevent the terminal 10 from beinginserted completely through the aperture 12 in the thin wall of thecasing 14.

Beneath the main body portion 18 and the flanged portions 26 of theterminal '10, there is a downwardly extending projection. Thisprojection of the terminal 10 is the terminal connector 28 to whichelectrical conductors (not shown) can be secured by numerous means, oneof which is soldering. The terminal connector 28 can have numerousconfigurations, but for representative purposes is substantiallyrectangular.

A jig 30 is shown by dotted line configuration in FIG. 1. The jig 30 canbe of any known type and is used primarily to support and position theterminal 10 in the aperture .12 so that the upper edges 32 of theflanges 26 of the terminal abut against the lower surface 34 of thethin-walled casing 14.

As shown in FIG. 2, a cylindrical punch 36, having a concentriccylindrical cavity 38 bored in the central portion of the punch 36, isdepicted as being partially lowered over the male connector portion 16of the terminal 10.

Edge 40 is formed at the junction of a cylindrical surface 39 of thecavity 38 and a bottom beveled surface 42 of punch 36. Beveled surface42 is of frusto-conical form being inclined at a slight angle relativeto a plane normal to the axis of rotation of the punch 36. The angularinclination of the beveled surface 42 will depend upon the material fromwhich the terminal is made. Edge 40 will engage the upper edge 44 of theshoulder 24 immediately adjacent to the base width of the male connectorportion 16, when there is a downward motion of punch 36. Edge 40 willcut into shoulder 24, and beveled surface 42 will peel the cut metaloutwardly.

It will also be apparent that the cavity 38 of the punch 36 must becylindrical in form. The diameter of the cavity 38 is determined by theamount of material to to be peeled from the shoulder 24 of the terminal110, and the width of the male connector 18 of the terminal 10.

In FIG. 2, the circular punch 36 is diagrammatically shown as beingresiliently mounted by means of spring 46. Punch 36 is mounted to adrive mechanism (not shown) that will rotate or spin punch 36 atvariable speeds; and, in addition, the drive mechanism impartsv arectilinear reciprocating motion to punch 36 so that: the punch hasrapid longitudinal movement in two direc-- tions. The spring 46 willlimit the impact pressure of punch 36 in the downward direction to aconstant value..

As shown in FIG. 3, a quick, rapid, light impact blow of punch 36 in thedownward direction combined with the spinning action of punch 36 willevenly peel and peen the shoulder portion 24 of the main body 18 of theterminal .10 away from the male connector portion 16. The beveled edge42 of the punch 36 will curl the peeled shoulder portion 24over so as toform an upper flange 48 to the main body 24 of the terminal 10. It is tobe noted that the curled and peened shoulder 24 will form a flange 48 onthe upper surface 22 of the wail of the casing 14.

The jig 30 will force the flange 26 of the terminal into engagement withthe lower surface 34 of the thinwalled casing 14 to insure properengagement with the lower surface 34 of the wall. In addition, thepeeling and spinning action of the punch 36 will draw as much of theshoulder portion 24 of the main body 18 of the terminal 10 out'of theaperture 12 as is exposed to further insure a tight engagement betweenthe upper surface 32 of the terminal flange 26 and. the lower surface'34 of the thin-walled casing 14. The action of the resilient spring 46on the punch will equalize the pressure on the bevelededge 42 to therebyinsure that each peened shoulder 48 will be subjected to the same lightoscillatory impact motion of the punch 36; and, in addition, to thespinning motion of the punch.

The male terminal .10 is shown in FIG. 4, with the punch 36 partiallywithdrawn from its. lowermost stroke. It is to be noted that the peenedshoulder 48, due to the spinning action, overlaps the upper surface 22of the casing 14 immediately adjacent to the aperture 12 so as to form atab 50 which is not in alignment with the flat surface of the terminal10. For purposes of representation, the peened shoulders in FIGS. 3 and4 have been enlarged relative to their true representations. Inactuality, the uppermost portion 52 of the peened shoulder issubstantially level with the upper surface 22 of the casing 14 and couldbe considered as being flared into the upper surface of the casing.

As shown in FIG. 5, the peened shoulder 48 is spread out over'theadjacent surface of the thin-walled casing 14, and is, in eflect,twisted slightly from the flat plane of terminal 10 so that the terminal10 cannot be withdrawn from the aperture 12.

Although not shown in the drawings, it will readily be apparent that asubstantially circular terminal having a circular shoulder about themale connector portion of the terminal could also be subjected to theaction of the punch as previously described. The circular terminal willhave its shoulder spread out to overlap the area immediately adjacent toa circular aperture in the thinwalled casing.

In addition, it is to be realized that numerous terminals can be mountedin a single jig, so that each terminal is inserted through anappropriate aperture in the casing. In this manner, several punches canbe mounted on one drive mechanism so that the numerous terminals can befastened to the casing in one operation.

While only one embodiment of the invention has been shown and describedherein, it will be apparent that numerous modifications and changes canbe made without departing from the scope of the invention as defined in,

the appended claims.

We claim:

1. The method of securing a flanged terminal post in an apertured casingwall which comprises, positioning the terminal with the flange abuttingagainst the easing wall and the terminal post projecting through theaperture and outwardly of the wall, simultaneously cutting and spinningthe projecting portion of the terminal post away from the main bodythereof until the spun portion engages the casing wall, and furthercutting and spinning the projection portion while simultaneously peeningthe spun portion into evenly stressed engagement with the casing wall.

2. The method of securing a flanged terminal post in an a ertured casingwall which comprises, positioning the terminal with the flange abuttingagainst the casing wall'and the terminal post projecting through theaperture and outwardly of the wall, simultaneously cutting and spinningthe projecting portion of the terminal post until the spun portion curlstoward and engages the casing wall and further cutting and spinning theprojecting portion while simultaneously peening the spun and curledportion of the terminal post into evenly stressed engagement with thecasing wall. 7

3. The method of securing a flat plate flanged terminal post in a slitaperture in a casing wall which comprises, positioning the terminal withthe flange abutting against the casing wall and the terminal postprojecting through the aperture and outwardly of the wall,simultaneously cutting and spinning oppositely disposed projectingportions of the terminal post until the spun portions engage said casingwall, to overlap the longitudinal ends of the slit aperture, and furthercutting and spinning the projecting portions while simultaneouslypeening the spun portions of the terminal post into evenly stressedengagement with the casing wall closely adjacent to the longitudinalends and sides of the slit aperture.

4. The method of securing a flat plate flanged terminal post in a slitaperture in a casing wall which comprises, positioning the terminal withthe flange abutting against the casing wall and the terminal postprojecting through the aperture and outwardly of the wall,simultaneously cutting and spinning oppositely disposed shoulder portionof the terminal post until the spun portions curl toward and engage thecasing wall, to overlap the longitudinal ends of the slit aperture, andfurther cutting and spinning the projecting portions whilesimultaneously peening the spun and curled portions of the terminal postinto evenly stressed engagement with the casing wall.

References Cited in the file of this patent UNITED STATES PATENTS a....i.. .h

1. THE METHOD OF SECURING A FLANGED TERMINAL POST IN AN APERTURED CASINGWALL WHICH COMPRISES, POSITIONING THE TERMINAL WITH THE FLANGE ABUTTINGAGAINST THE CASING WALL AND THE TERMINAL POST PROJECTING THROUGH THEAPERTURE AND OUTWARDLY OF THE WALL, SIMULTANEOUSLY CUTTING AND SPINNINGTHE PROJECTING PORTION OF THE TERMINAL POST AWAY FROM THE MAIN BODYTHEREOF UNTIL THE SPUN PORTION ENGAGES THE CASING WALL, AND FURTHERCUTTING AND SPINNING THE PROJECTION PORTION WHILE SIMULTANEOUSLY PEENINGTHE SPUN PORTION INTO EVENLY STRESSED ENGAGEMENT WITH THE CASING WALL.